Project Summary Chronic respiratory diseases (CRD) kill more than 4 million people every year and erode the health of millions worldwide. These diseases incur massive healthcare expenditures while affecting quality of life and productivity. Despite the morbidity and mortality associated with CRD, a clear understanding of the biology of pathogenesis remains elusive. An important respiratory defense mechanism, mucociliary clearance is driven by hundreds of multiciliated cells (MCCs) that beat in a coordinated fashion to clear the airway of infections and toxins. However, defects in cilia growth or function can lead to CRD. Further, cilia loss due to infection and inflammation can compound and exacerbate CRD. Interestingly, these cilia have the ability to regenerate ameliorating the symptoms of affected individuals. However, the molecular mechanisms of cilia regeneration are poorly understood. In my lab, I plan to study the genetic, molecular and cellular mechanisms that regulate cilia assembly and regeneration in the MCCs in the context of disease, specifically, mucociliary clearance diseases. My long-term goal is to become an independent investigator who is a leader in the field of cilia biology. To achieve this goal, I will analyze the ciliogenesis gene, CCDC11. I will also obtain crucial training in cilia biology, advanced microscopy and biochemistry and seek out professional development activities to help position me to be a strong academic candidate and establish a successful independent research program. To obtain the training I need to be well-versed in cilia biology, I will engage in the following activities: 1) interact with my collaborators, who are experts in cilia, actin and tubulin biology: 2) actively participate in Cilia Group Meetings as well as other conferences on cilia biology and 3) develop an independent research program on cilia regeneration. I will seek out professional development opportunities such as workshops on writing an R01, postdoc job mentoring program, and take every opportunity to present my work both locally and at national meetings to develop strong collaborations and bring visibility to my work as I prepare for an academic career. The additional training time afforded to me by the K99/R00 grant would also allow me to further develop my independent research program. First, I will study the role of CCDC11 in cilia assembly in the MCCs using an integrative approach of advanced imaging, biochemistry and multi-model system analysis. These new skills will be instrumental in studying new cilia genes in my own lab. I will also develop Xenopus as an in vivo cilia regeneration model, which will then become the basis of my future independent research. Specifically, I will study cilia regeneration at multiple levels, cell behavior during regeneration using live imaging, spatial and temporal regulation of cilia regeneration using known ciliogenesis genes and identifying novel cilia assembly/function and regeneration genes using multiple different methods including patient driven gene discovery.